BSB Seminar: A decade of research into Acinetobacter efflux pumps

Karl Hassan, The University of Newcastle


The Acinetobacter genus includes at least 70 named species that occupy environments which differ broadly in nutrient composition, water availability, temperature and other abiotic characteristics. The best studied Acinetobacter species are human pathogens, including the WHO top priority pathogen Acinetobacter baumannii. A consistent theme of my research over the past decade has been in studying the efflux proteins encoded by Acinetobacter, particularly A. baumannii. Efflux pumps can be very promiscuous in substrate recognition, and therefore a single pump can fulfil multiple functional roles in a cell. Efflux pumps contribute to the high levels of antibiotic resistance seen in clinical Acinetobacter isolates, but many of these pumps are highly conserved across the genus, suggesting important primordial functions. In this talk I will describe our group’s contributions to the field of Acinetobacter efflux over the past decade, including the discovery of novel efflux pump functions, their regulatory influences, and the discovery of new efflux proteins from one (or more) new families of proteins.


Karl Hassan is an ARC Future Fellow at the University of Newcastle. Prior to Newcastle, Karl held research fellowships at the University of Leeds and Macquarie University. Karl is a molecular microbiologist with expertise in functional genomics and protein biochemistry/biophysics. Karl’s research broadly examines mechanisms of small molecule transport in bacteria, the physiology of bacterial cell envelopes and bacterial global regulatory networks. Karl has current research projects investigating drug resistance in Gram-negative bacteria, microbial metal ion homeostasis, plant pathogen suppression by biocontrol bacteria, hydrocarbon bioremediation, and synthetic biology tools for exploiting bacteria in the production of high-value chemicals.